Use similar interface to access gitolite

Simplified gitolite handle logic
Stubn over monkeypatch
Stub only specific methods in Gitlab:Gitolite
Moved grach auth to lib
added specs for keys observer
removes SshKey role

app/models/key.rb

@@ -1,7 +1,6 @@
 require 'digest/md5'
 
 class Key < ActiveRecord::Base
-  include SshKey
   belongs_to :user
   belongs_to :project
 
@@ -50,6 +49,10 @@ class Key < ActiveRecord::Base
       user.projects
     end
   end
+
+  def last_deploy?
+    Key.where(identifier: identifier).count == 0
+  end
 end
 # == Schema Information
 #

app/models/protected_branch.rb

@@ -1,4 +1,6 @@
 class ProtectedBranch < ActiveRecord::Base
+  include GitHost
+
   belongs_to :project
   validates_presence_of :project_id
   validates_presence_of :name
@@ -7,7 +9,7 @@ class ProtectedBranch < ActiveRecord::Base
   after_destroy :update_repository
 
   def update_repository
-    Gitlab::GitHost.system.update_project(project.path, project)
+    git_host.update_repository(project)
   end
 
   def commit

app/models/users_project.rb

@@ -1,4 +1,6 @@
 class UsersProject < ActiveRecord::Base
+  include GitHost
+
   GUEST     = 10
   REPORTER  = 20
   DEVELOPER = 30
@@ -58,9 +60,7 @@ class UsersProject < ActiveRecord::Base
   end
 
   def update_repository
-    Gitlab::GitHost.system.new.configure do |c|
-      c.update_project(project.path, project)
-    end
+    git_host.update_repository(project)
   end
 
   def project_access_human